To date, elaborate systems are found which allow the onboard electrical energy to be managed. An aircraft generally comprises a plurality of electrical systems which are supplied with power by sources that allow electricity to be generated and loads that use this electrical energy. Among the sources are the main generators associated with the aeroplane's engines. There are likewise storage devices such as batteries. Certain loads may be regenerative according to their phase of use.
Jumbo jets have an increasing amount of onboard electrical equipment forming loads for the electrical systems. This equipment is very varied in nature and the energy consumption thereof is highly variable over time. By way of example, internal air-conditioning and lighting systems are in almost continuous operation, whereas redundant safety systems such as aerofoil controls are used only exceptionally or in phases of limited duration. The storage devices are also considered to be loads when they receive energy from the sources.
There are systems which allow management of the priorities among the loads when the electrical demand is higher than the sources are able to provide. By way of example, it is possible to temporarily shed air conditioning in favour of aerofoil controls when the use of the latter is vital to piloting the aeroplane.
Moreover, in an aircraft, there are potential sources of thermal energy which are not or very rarely used.